<div class="card">
    <div class="xs-card-content">
        <div class="content">
            <form action="/search" method="POST">
                <div class="field is-grouped">
                    <p class="control is-expanded">
                        <input name="key" class="input" type="text" placeholder="请输入 试题标题/问题 搜索答案">
                    </p>
                    <p class="control">
                        <button type="submit" class="button is-link">搜索</button>
                    </p>
                </div>
            </form>
        </div>
    </div>
</div>